Mountain Hardwear's new StretchDown jackets use stretch-welded channels that trap more warmth than standard stitching.

The jacket is also made from a special kind of down that helps retain the same high-performance even when wet.

The resulting jacket, which I got to try, is somehow both the thinnest and warmest winter jacket I've used yet.

Instead of "snow days" my Minnesotan childhood was filled with "cold days" — the difference being that "cold days" are when it is literally unsafe to leave children outdoors waiting for the school bus. So I'm familiar with cold weather and how to prepare for it — and as nearly all my youthful photos may suggest, preparation often requires you to invest in a lot of puffy and cumbersome down.

However, perhaps nothing has impressed me as much — or wormed its way into my day-to-day life — like Mountain Hardwear's StretchDown Jacket. The company sent me one to test, and it has quickly replaced almost every other winter jacket I own. It is impossibly warm for its total lack of bulk, and it manages to actually look slimming without the concession of tailoring restricting my mobility. It comes in five everyday colors you'd actually want to wear, and the lack of noticeable logo is a nice aesthetic touch. It's also been engineered to insulate you just as well while wet as it does dry, so a rain shower while you're out grabbing lunch won't leave you miserable and clammy.

Mountain Hardwear notes that the StretchDown jackets are especially great for alpine climbing, backpacking, and hiking, and I can absolutely see that as someone who loves each of those activities. But even more importantly for a winter jacket investment, its lack of bulk and color scheme make it fantastic for everyday use in an urban area. Whenever I want warmth, durability, and a nice silhouette — which is essentially all of the time — I find myself grabbing this instinctively.

The jacket is incredibly warm even while being thin as well as stretchy even while being tailored. If you ask them how, the company would probably point to some of that aforementioned technology; StretchDown jackets use the new stretch-welded channel construction to trap warmth better than standard stitching and dynamic stretch knit for unrestricted movement. Q.Shield Down resists losing heat in wet conditions. The first-of-its-kind stitchless design keeps warmth from escaping.

I got the small, my typical size in winter jackets, and have found it true to size, as most other reviews indicate. I've layered chunky sweaters underneath without issue, but if you really plan to pack in heavy layers, you might consider sizing up as the fit is still somewhat tailored.

I've been wearing winter jackets all my life, but this one is so far my favorite for its clean look, flattering fit, noticeable comfort, and great insulation.

It doesn't come cheap at $300, but in terms of competitors, it's about what you'd expect to pay for high-level performance. If you're looking for a sleek, versatile jacket that also delivers on incredible warmth and comfort, the StretchDown is one of the best options on the market.

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